Improvement in calico-printing rollers



J. HOPE. Calico-Printing Rollers.

No. 196,149. Patented Oct. 16, 1877.

-WITNESSES. INVENTOR.

NJETERS, FHOTO-LITHOGRAPHER. WASHINGTON, n C

' UNITED STATES PATENT OFFICE.

JOHN HOP E, OF PROVIDENCE, RHODE ISLAND.

IMPROVEMENT IN CALICO-PRINTING ROLLERS.

Specification forming part of Letters Patent No. 196,149, dated October16, 1877; application filed January 20, 1877.

To all whom it may concern:

Be it known that I, JOHN HOPE, of the city and county of Providence,State of Rhode Island, have invented certain new and useful Improvementsin Mandrels for CalieoPrintin g Rolls; and I hereby declare that thefollowing is a full, clear, and exact description of the same, referencebeing had to the accompanying drawings, forming part of thisspecification.

Figure l is a view of my improved mandrel. Fig. 2 is a longitudinalsection of the same.

The invention has reference to an improvement in mandrels forcalico-printing rolls and consists in securing to a shaft a concentrictube or cylinder, made slightly tapering, and of such diameter that athin copper shell bored out to fit the mandrel may be secured to thesame by frictional contact, and the same mandrel may be used for anynumber of copper shells.

In the drawings, a is a shaft, provided with bearings. 71 b are twoannular rings, shrunk or welded on the shaft a, or otherwise firmlysecured to the same. 0 is a slightly-tapering cylinder or tube, firmlysecured to the annular rings or collars lg I), and thus by them to theshaft (1..

The cylinder or tube 0 may be shrunk or welded to the annular rings 1)b, and the shaft a may be of less diameter between the annular rings (1(1 than at the bearings; and as the cylinder or tube 0 is ofconsiderable diameter and firmly secured to the shaft,=-a mandrelpresenting alarge surface, of considerable diameter, strong and firmlybraced, and lighter than the usual mandrel, is produced, on which a thincopper shell can be placed with little trouble, as a slight taper willsecure the same by frictional contact more firmly than on amandrel ofthe usual construction.

By the use of this mandrel thin copper she may be used forcalico-printing, and the large investment in copper avoided; and as thecopper shells are not permanently secured to the mandrel or to thecylinder or tube 0, the copper rolls are not injured by the expansion orcontraction of different metals. The copper shells, beinglighter, areeasily handled, and the mandrel, being also lighter and of greaterdiameter than mandrels of the usual construction, the light copper rollsare more firmly supported at all parts oftheir surface, and less forceis requlred to bring the same into true frictional contact with the tubeor cylinder 0, and are not liable to be displaced.

I am aware that light or thin copper cylinders have been used, and I amaware that such cylinders have been strengthened by concentriccylinders; butsuch copper cylindersv and the concentric cylinders haveheretofore JOHN HOPE.

Witnesses J OSEPH A. MILLER, OSCAR LAPHAM.

